The proposed research will initiate a systematic investigation of probable in vivo regulatory mechanisms, which control the rate accumulation of the disaccharide, trehalose and its compartmentation during development in the cellular slime mold, Dictyostelium discoideum. The specific aims to be achieved will be: (1) to purify T6P synthetase to homogeneity and to characterize the physical, chemical and kinetic properties of the enzymes; (2) to compare the effects of heparin and the Dictyostelium acid mucopolysaccharide on the catalytic properties and the state of aggregation of the synthetase; (3) to obtain antibody specific for T6P synthetase and to quantitate the levels of this enzyme in vitro during development with the specific antisera, and (4) to localize intracellular T6P synthetase during development by application of the techniques of immunoferritin and indirect immunofluorescent staining using purified specific antibody elicited against this enzyme.